SPARTAN IS RECALLING CERTAIN MODEL YEAR 2008 THROUGH 2010 GLADIATOR AND METROSTAR INCOMPLETE FIRE APPARATUS CHASSIS CABS MANUFACTURED FROM NOVEMBER 14, 2008 THROUGH MAY 25, 2010, EQUIPPED WITH TANDEM REAR AXLES AND ELECTRONIC STABILITY CONTROL (ESC). THE VEHICLES FAIL TO MEET THE SERVICE BRAKE RELEASE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, “AIR BRAKE SYSTEMS.” SPECIFICALLY, ADDITIONAL VALVING REQUIRED FOR THE ESC SYSTEM REDUCED THE AIR FLOW AND VOLUME TO THE BRAKE CHAMBERS RESULTING IN SLOWER SERVICE BRAKE RELEASE TIMING.